Field of the Invention
The invention relates to an electrostatic coating process, and more specifically, to a process for electrostatically coating workpieces with powder materials.
In electrostatic powder spraying, the powder particles are positively or negatively charged. The coating layer thickness which can be achieved with one coating operation is generally less than 500 .mu.m, because the charge of powder particles that have already been applied has a repulsion effect on subsequent powder particles bearing a charge of the same sign. For many technical applications, such as electrical or thermal insulating layers, the coating thickness achievable in this way is inadequate. In that case, multiple coating with coat sintering is required.